The present invention relates to a power supply device, and a technology effective when applied to a multiphase type switching power supply device that converts a high voltage to a low voltage, for example.
There has been described in a patent document 1, for example, a semiconductor device in which a power MOSFET, a drive circuit for driving the power MOSFET, and a control circuit for transferring a switching control signal to the drive circuit are mounted in one package (refer to FIGS. 1 and 2). This semiconductor device is capable of multiphase operation (refer to FIG. 15).
There has been described in a patent document 2, a multiphase type DC/DC converter device in which a plurality of converter control ICs are used to supply power to a load in phases different from one another respectively (refer to FIG. 1).